Hi Mitchell,
thank's a lot. Now I see my mistake. I was looking for a way to not define/create everything in the Launch method.
Now I took a closer look to the 'Ext.application' API and found the headline 'Telling Application about the rest of the app' and that was the part I should have looked first. Probably that would be worth a link in the getting started guide.

I hope, the "upcoming application architecture guide" will come out quick.